It wasn’t long after Diana Nyad emerged from the ocean in Florida after a historic 53-hour, 110-mile swim from Cuba that doubters started to question her record-setting accomplishment.

Was the 64-year old swimmer actually in the water the whole time? Could she have made the crossing as quickly as she claims? With a crew that helped feed her and put on a special jellyfish suit, did her feat qualify as truly “unassisted?”

From topping Mt. Everest to discovering the source of the Nile, nearly every new “first” has been immersed in debate and controversy -- perhaps because it can be hard to believe that someone has done something extremely challenging that others have failed to do before.

In modern times, skepticism has spiked with every new example of cheating, such as the use of performance-enhancing drugs. Even as our culture elevates athletes to superstar status and follows their every move, we are quick to watch them fall from grace and then spread real-time gossip about what happened, said Dan Lebowitz, executive director of the Center for the Study of Sport in Society at Northeastern University in Boston.

“We live in an era of suspicion about anything accomplished,” Lebowitz said. “We get caught up in loving the rise and loving the fall even more. Some of the negative qualities in human nature celebrate the fall more than the feat.”

Examples of discounted athletic endeavors are numerous.

Cyclist Lance Armstrong was long hailed as a national hero with an unprecedented seven consecutive Tour de France wins until evidence that he doped stripped him of his titles and banned him from competitive sports.

Likewise, baseball fans marveled at Barry Bonds’ home-run records until he became wrapped up in a steroids scandal. Same goes for New York Yankees phenom Alex Rodriguez. And Canadian runner Ben Johnson notoriously disappointed spectators who marveled at his 100-meter world records after it turned out that he had doped.